The technology of the present disclosure relates to a gear device, a drive device and an electronic device provided with the drive device.
In an electronic device such as a multi function peripheral or a printer, a drive device provided with a gear device is installed in order to transmit a torque of a motor to a roller (e.g., a photosensitive drum). The gear device includes a rotor and an armature. The rotor and the armature are coupled or decoupled by an electromagnetic force, thereby controlling rotation of the gear device.
For example, there is proposed a technology in which the rotation direction of a motor of an electronic device is switched between a clockwise direction and a counterclockwise direction. With this technology, when a drive device is in operation, a rotor and an armature are coupled by an electromagnetic force. Regardless of the rotation direction of the motor (namely, regardless of whether the rotation direction of the motor is clockwise or counterclockwise), a gear device rotates in a state in which the rotor and the armature make close contact with each other.